Adult bicycles normally are equipped with a single seat upon which the cyclist may sit while peddling and steering. Often parents wish to have a child accompany them while cycling. Although the parent may strap the child to his or her back in papoose fashion, it is more common to have the child sit on an auxiliary seat that is attached to the bicycle. Such a seat has commonly been mounted over the rear fender with the child's legs straddling the rear wheel. This arrangement, however, has a number of disadvantages. For example, the view for the child is mainly that of the back of the adult rather than the passing scene. Since the child is behind the cyclist, the cyclist must turn around in order to talk with or to check on the child's security. There is also the chance of the child's foot striking the rear wheel. This positioning of the child also moves the center of gravity of the loaded bike so far to the rear as to seriously affect stability. This design is expensive, requires much time and skill as well as a number of tools to attach it. Equally, removal is difficult and time consuming.
For these reasons child seats have more recently been designed to be mounted in front of the cyclist and just behind the head tube and handle bars. This offers much improvement over the rear attached child seats because of the shift of the child's weight from the rear to the center of the bicycle. The major failure of all of the centrally placed child seats invented thus far has been severe inherent design lateral instability. These designs create no reasonable safety for the child and equally increased operational hazards to the cyclist.
Where the cyclist is interested in transporting objects other than a child, the same problems arise as to instability. Notwithstanding the improved results of positioning a load to the center of the bicycle between the seat and head tube, current inventions fail to consider the import of accounting for lateral stability. Examples of such prior designs are shown in U.S. Patents as follows:
In U.S. Pat. No. 3,902,737 entitled CHILD CARRIER AND MOUNTING ASSEMBLY FOR BICYCLE by I. Berger and K. Welter, the child's seat is attached by clamps to the cylindrical head tube (steering column) providing no assured lateral stability. The seat may be allowed to swing outward to the left or right causing improper displacement of weight.
In U.S. Pat. No. 4,305,532 entitled UNIVERSAL BICYCLE CARRIER by J. Reminger, the child's seat is attached to a 4" wide platform that merely sits either on the bicycle's upper structural support tube of a male style bicycle with no attachment, or loosely wedges between the head tube and seat post of a female style bicycle. The wedge in front of the platform that rests against the sides of the head tube is inadequate to provide vertical or rotational stability for the child seat. Moreover, the mechanism suggested for use as foot stirrups has no structural functionality and although its design straddles the upper structural support tube of both a male and female bicycle, it is only resilient wire having flexibility for removable attachment to the seat platform and does not strattle the bicycle's lower structural support bar.
In yet another design, U.S. Pat. No. 4,632,453 entitled AUXILIARY SUPPORT SYSTEM FOR BICYCLE PASSENGER by J. Robbin and J. Robbin, the child's seat attaches to the top tube and has nothing in the design to assure against severe rotational instability. Likewise, the foot clips bar is attached to the head tube. There is no assurance against rotational instability here, either. Moreover, essentially no modem bicycles have an amount of free space around the head tubes necessary to secure such foot clips.
In still another U.S. Pat. No. 4,919,479 entitled APPARATUS. FOR CARRYING A PASSENGER ON A BICYCLE by E. Loewke and D. Loewke, the child's seat rests upon the upper structural support tube and is centrally located. It has one attachment to hold down the forward part of the design but nothing to secure the rear end which loosely straddles the rear post. The latter design is insufficient to prevent lateral wobbling and with one mild-to-moderate bump the rear of the design may well lift away from resting on the upper tube possibly allowing the child to fall to the ground.
In U.S. Pat. No. 5,104,188 entitled BICYCLE SEAT FOR CHILDREN by M. Jefferson, the child's seat rests centrally and around the top tube, secured by one clamp. Like prior designs, inherently this cannot guarantee against rotational instability. Moreover, the vertical brace for use on female style bicycles is designed only to strattle the bicycle's upper structural support tube allowing for inherent lateral instability.
Finally, in U.S. Pat. No. 5,330,215 entitled CENTER-MOUNTED PASSENGER SEAT FOR BICYCLE by M. Bishaf and J. Faulhaber, the child's seat has a rearward attachment by thin rods to the seat post and the forward position merely rests atop the top tube. Not only will the rods be unable to prevent the child's seat from tilting side to side, there is nothing to prevent upward instability of the forward portion of the design.
Accordingly, it is seen that a centrally located auxiliary seat for a bicycle of relatively simple economic construction, yet possessing a high degree of lateral stability, remains in need. It is to the provision of such therefore, that the present invention is directed.